Field of the Invention
The present disclosure relates to traffic information collection, and more specifically, to providing accurate real-time traffic information.
Background
Drivers obtain traffic conditions through electronic traffic status signs installed on the road, traffic radio stations, or electronic navigation guidance such as the global position system (GPS). Thus, the real-time traffic information enables the driver to save time and fuel. Further, the real-time traffic information can be linked with traffic signaling systems at intersections to reduce traffic congestions. Accordingly, the accurate real-time traffic information can provide not only time and fuel savings for individual drivers, but also reduce energy use and air pollution at the regional and national level. For autonomous vehicles, generating and providing large-scale, real-time traffic information at the regional and/or national level is important in establishing the route guidance, in addition to the basic autonomous operations of the vehicle. Currently, the traffic information collection is done using various different methods including a closed-circuit television (CCTV) method and a loop detector method.
For the CCTV method, the CCTV cameras can be installed on designated roads and the videos collected from the CCTVs are transmitted to a central server. The operators may divide the videos into local zones and visually confirm and input the real-time traffic conditions. However, the CCTV method requires a lot of manpower and labor costs to provide a city-wide or nationwide coverage of the real-time traffic information. Further, providing the real-time traffic information can be difficult because it requires continuous, real-time visual monitoring.
For the loop detector method, the loop coil sensors can be installed on roads to sense and collect the movement of vehicles on the road and to combine the movement with information from the location sensors installed in public transportation vehicles such as buses and taxis. Although this method may provide more accurate and automatic traffic volume measurement than the CCTV, the cost of installation and maintenance can be prohibitive. Further, transmitting the collected data from the loop detectors to the central server may require a high-speed network, which can be very expensive.